Randomly came across UpTake.com. It's a new travel search site with a twist. They take a bit more personalized approach by factoring in your travel preferences. More from their site:
UpTake.com is a travel search and discovery site - the first step for travelers to decide where to go, where to stay or what to do. We help users make informed decisions about what best fits their travel preferences. We scoured more than 1,000 sites to collect 400,000 places to go, things to do and places to stay in the U.S. Then we analyzed and organized over 20 million travelers' opinions to enable search based on exact travel requirements and preferences.
They are still in beta, but their more personalized approach is a good path their differentiation as long as their pricing search results are competitive. You can read their travel blog here.